The X-Men and Inhumans have been battling over the Terrigen Cloud, which kills mutants but gives Inhumans their powers.
1. The Terrigen Cloud Is Gone.
After being told that the Terrigen Cloud was going to make the planet inhabitable for mutants, Medusa uses a device created by Moon Girl and Forge to get rid of it.
4. Emma Frost Is a Villain Again.
After the cloud is removed, Emma still wants revenge on the Inhumans for Cyclops's death, and attacks them with specially made sentinels that target Inhumans instead of mutants. The X-Men and the Inhumans team up to defeat her, and she goes on the run.